Hey, I don't know if you are a father or mother but we are all here to support each other on this site. I too am battling depression, along with anxiety, and bipolar disorder. The gift of having a child is watching them grow up. Do what you feel necessary, but remember this your child would rather be homeless with you than grow up without you.
Lifes hard but you should make it easier for your child by being there. Their are many more great moments you can have with your child. First day of kindergarten, First day of Middle School, Prom, Wedding , and Grandchildren. There's a higher power somewhere and we're here for a reason. I hope you make the right decision.